Depression resilience limited the emergence of resistant extinction phenotype. Particularly, during the first week of extinction training, SDPS‐resilient animals performed midway of the two other groups, mimicking the effect of SDPS in the general population.20 From then onwards, extinction responding in SDPS‐resilient individuals mirrored the performance of control rats, indicating that in these animals, extinction of previously learned but currently inappropriate behavioral patterns is intact. This is in accordance with the notion that resilience to severe stress is characterized by facilitated extinction of nonrelevant information,36 ie, adaptive extinction learning. Notably, facilitation of reversal learning, namely, a swift from learned responses toward the most adaptive ones, is observed following administration of tricyclic antidepressants37 and of selective serotonin reuptake inhibitors.38 Thus, it is possible that in SDPS‐resilient animals, extinction learning is mediated via adaptations of the serotoninergic and noradrenergic systems that promote cognitive/behavioral flexibility.
